import matplotlib.pyplot as plt
import numpy as np
import pandas as pd

score = ['60-69', '70-79', '80-89', '90-100']
people = [2, 10, 18, 4]
plt.title('pingtu')
plt.pie(x=people, labels=score, explode=(0.1, 0, 0, 0))
plt.legend(score, loc='upper left')
plt.show()